1. Field of the Invention
The invention relates to removing radioactive plastic wastes and more particularly, refers to new and improved method and apparatus for removing radioactively contaminated ion exchanger filter materials by embedding in a bituminous solidification substance.
2. Description of the Prior Art
Radioactive plastic wastes have heretofore been disposed of by adding the wet plastic waste to hot bituminous substances thereby simultaneously drying the waste and covering the waste with bitumen. The bitumen covered waste is filled into containers such as barrels, which serve for final storage.
The methods known up to now (cf. the German Published Non-Prosecuted Applications DT-OS Nos. 14 64 476, DT-OS No. 14 64 859, DT-OS No. 21 65 510 and the German Published Prosecuted Applications DT-AS No. 1 589 839 and DT-AS No. 1 614 071) largely operate at relatively high temperatures, of the order of 160.degree. or higher. One important reason for this is to keep the bitumen as "thin" as possible, i.e. the bitumen should be non-viscous to thoroughly coat and encapsulate the wastes. In addition, one wants to perform a drying process with the bitumen in order to achieve a tight enclosure of the radioactive plastic wastes that are to be embeded. This tight enclosure is necessary because the danger of leaching in the event of an inrush of water into the storage place is to be avoided. High temperatures and the need for drying, however, are uneconomical, and may also have undesirable consequences for reasons of chemical reactions.
Simultaneous drying and encapsulating at higher temperatures as commonly practiced heretofore has the following disadvantages:
The resins were decomposed by chemical reaction and gases (e.g., amines) were liberated in the process.
These gases were an increased pollutant on the environment as they have a penetrating odor and are explosive.
As the product of resin and bitumen, produced at higher temperatures, would strongly foam due to the formation of gas, the safety of pouring was jeopardized.
The dosaging of moist resins was difficult because of clotting and was not operationally safe.